Deicing solution

ABSTRACT

A de-icing and anti-icing composition in the form of an aqueous solution which includes sugars, and an inorganic freezing point depressant in the form of a chloride salt.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation of U.S. Ser. No. 10/444,559 (now allowed), filedMay 23, 2003 which is a continuation of U.S. Ser. No. 10/260,808, nowU.S. Pat. No. 6,582,622, filed Sep. 30, 2002 (Granted Jun. 24, 2003),which is a continuation-in-part of U.S. Ser. No. 10/212,319, now U.S.Pat. No. 6,596,188, filed Aug. 5, 2002 (Granted Jul. 22, 2003), and acontinuation-in-part of U.S. Ser. No. 10/212,318, now U.S. Pat. No.6,599,440, filed Aug. 5, 2002 (Granted Jul. 29, 2003), which both are acontinuation-in-part of application U.S. Ser. No. 09/971,163 now U.S.Pat. No. 6,440,325 and U.S. Ser. No. 09/971,165 now U.S. Pat. No.6,436,310 both filed on Oct. 4, 2001 (Granted Aug. 27, 2002 and Aug. 20,2002, respectively), which are both a continuation-in-part of U.S. Ser.No. 09/755,587, now U.S. Pat. No. 6,299,793, filed Jan. 5, 2001 (GrantedOct. 9, 2001), which is a continuation-in-part application of U.S. Ser.No. 09/224,906 filed on Jan. 4, 1999, now abandoned and U.S. Ser. No.60/070,636 filed Jan. 7, 1998, the entirety of each of the aboveapplications which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The current state of the art for coping with snow and ice on roadsusually involves applying a deicer material such as a salt to the roadsurface. Sometimes antiskid materials such as sand or other aggregatessuch as gravel are added with or without a salt.

The use of salt and compositions having high concentrations of salt,cause an undesirable corrosive effect on vehicles, the road surface, andthe environment with respect to the run off of water containing saltwhich contaminates the surrounding land and water.

Considering the above problems associated with salt formulations, therehas been a continuing need for a deicing composition or formulationwhich can effectively melt snow and ice yet which reduces the corrosionand environmental contamination referred to above. In response to theabove problems associated with the use of road salt, the prior art haslooked to alternative formulations which are less corrosive and moreenvironmentally friendly.

U.S. Pat. No. 5,635,101 (Janke et al.) relates to a deicing compositioncontaining a by-product of a wet milling process of shelled corn. Cornkernels are steeped or soaked in a hot solution containing small amountsof sulfurous acid. The corn kernels are separated from the steep waterand steep water solubles are used in the production of a deicingcomposition.

U.S. Pat. No. 4,676,918 (Toth et al.) relates to a deicing compositionwhich comprises a mixture containing at least one component selectedfrom a number of chlorides or urea and an admixture of waste concentrateof alcohol distilling that has a dry substance content of from 200 to750 g/kg and from 10% to 80% by weight of water.

U.S. Pat. No. 6,080,330 (Bloomer) teaches a composition for use inpreventing the formation of ice or snow on outdoor surfaces, such asroadways or aggregate stockpiles, and also for deicing surfaces uponwhich snow or ice has formed. The composition is formed from a wasteproduct of the process of removing sugar from sugar beet molasses, alsoknown as desugared sugar beet molasses.

The Janke et al., Toth et al. and Bloomer materials are naturallyoccurring substances with hundreds (if not thousands) of components suchas complex carbo-hydrates, starches, sugars, proteins etc. and arenormally used with a salt.

The above de-icing solutions now being introduced in the field employagricultural residues e.g., corn based distillers solubles and solublesfrom the corn wet milling industries. These naturally occurringsubstances, which also include brewers condensed solubles, are extremelyvariable in composition, viscosity, film forming tendency, freezingtemperature, pH etc., and consequently give varying performance whenused in de-icing solutions. Depending upon the source and batch, thesematerials at low temperatures sometimes exhibit such resistance to flowthat they cannot be applied evenly to a road surface or mixed with achloride, rendering them virtually unsuitable for use.

Furthermore, these patents utilize materials which have highlyundesirable or unnecessary ingredients leading to practical difficultiesby manufacturers and users, such as stratification in storage,biological degradation, odor, plugging of filters and spray nozzles andenvironmental difficulties e.g. high biological oxygen demand due to thevery high organic contents (about 40% by weight), presence of phosphoruscompounds and heavy metals.

To improve quality and performance, and to meet current mandatedstandards, there is an immediate need for synthetic, chemically modifiedthickeners, and carefully purified materials which can be substitutedfor the currently used agricultural residues. Such a formulation wouldimprove performance and reduce metal corrosion, spalling of concrete,toxicity and addresses environmental concerns.

It is therefore an object of the present invention to provide a deicingformulation which exhibits improved performance standards whichovercomes the prior art problems described above.

It is a further object of the present invention to provide a deicingformulation which utilizes a synergistic combination of a low molecularweight carbohydrate and an inorganic freezing point depressant.

It is another object of the present invention to provide a deicingformulation which utilizes a low molecular weight carbohydrate toprovide for improved ice melting properties and exhibits less corrosion.

It is a further object of the present invention to provide a deicingformulation which provides consistent physical and chemical properties,thereby assuring consistent quality and performance.

It is another object of the present invention to provide an economical,highly effective deicing formulation.

SUMMARY OF THE INVENTION

The present invention is based upon the discovery that low molecularweight (about 180 to 1,000) carbohydrates when used with an inorganicfreezing point depressant such as a chloride salt has a synergisticeffect upon freezing point depression. The formulation ofdeicing/anti-icing compositions employs carbohydrates of less than about1,000 molecular weight, such as glucose/fructose, disaccharides,trisaccharides, tetrasaccharides, pentasaccharides, hexasaccharides, andmixtures thereof. The broader operative range for the carbohydratemolecular weight is from about 180 to 1,500, with the range of about 180to 1,000 being preferred.

The basic composition of the present invention consists of at least thefirst two of the following three components in aqueous solutiondepending upon ambient weather conditions, terrain, nature and amount offreezing/snow precipitation, and environmental concerns:

-   -   (1) Inorganic freezing point depressants preferably in the form        of chloride salts which include magnesium chloride, calcium        chloride and sodium chloride. Metal acetates e.g. calcium        magnesium acetate, and other suitable acetates may also be used.    -   (2) Low molecular weight carbohydrates in the 180 to 1,500 range        (180-1,000 preferred). These carbohydrates can be obtained from        a wide range of agricultural based products such as those        derived from corn, wheat, barley, oats, sugar cane, sugar beets        etc.    -   (3) Thickeners are used in certain applications as the third key        component to increase the viscosity of the composition so that        the liquid remains in contact with the road surface or with the        solid particles in piles of rocksalt/sand, or        rocksalt/aggregates, or salt alone, or sand or aggregate.        Thickeners are mainly cellulose derivatives or high molecular        weight carbohydrates. Typical molecular weights for cellulose        derivatives are for methyl and hydroxy propyl methyl celluloses        from about 60,000 to 120,000 and for hydroxy ethyl celluloses        from about 750,000 to 1,000,000. Carbohydrate molecular weights        range from about 10,000 to 50,000.

These components are used in an aqueous solution in the followingconcentrations: Weight % Carbohydrate 3 to 60 Inorganic Freezing PointDepressant 5 to 35 Thickener 0.15 to 10.

In a further embodiment of the present invention it has been found thatcertain low molecular weight sugars function as highly effectivecarbohydrates in the above formulations.

The above described compositions provide a de-icing and anti-icingformulation which can be formulated more uniformly to provide for moreconsistent properties from batch to batch, while at the same timeproviding for increased ice melting properties.

DETAILED DESCRIPTION OF THE INVENTION

In the development of the present invention it was determined that thepredominant organic constituents in the prior art formulations describedabove were carbohydrates, and in one series of tests, Brewers CondensedSolubles (BCS), which was selected as a test sample, was diluted withwater and separated into several fractions by the addition of increasingamounts of an ethanol/methanol 85/15 v/v mix. The characteristic of thevarious fractions and their freezing points when mixed with 15%magnesium chloride are tabulated below. TABLE 1 % ethanol/ % Freezingmethanol % Carbo- Point Sample added Solids hydrates ° F. ° C. Brewers(BCS) NIL 43.6 43.1 −31.9 −35.5 Fraction A Precipitate 60 5.3 3.8 −10.1−23.4 Fraction B Precipitate 74 3.7 3.2 −10.8 −23.8 Fraction CPrecipitate 82 2.8 2.1 −10.3 −23.5 Fraction D Precipitate 85 1.3 0.6−9.9 −23.3 Fraction E Solubles 85 30.7 29.8 −22.7 −30.4

Fraction A consisted of essentially insoluble, high molecular weightpolysaccharides, whereas Fractions B to D inclusive gave gummy residuesof polysaccharides. Fractions A to D had little effect upon freezingpoint depression. Fraction E, the largest component, had a considerableeffect upon freezing point and is a mixture of lower molecular weightpolysaccharides.

Fraction E was also examined for ice melting characteristics at 25° F.(−4° C.) in admixture with magnesium chloride employing SHRP H-205.2Test Method for Ice Melting of Liquid Deicing Chemicals. TABLE 2 Lbsweight ice melted per Deicing Solution lb weight of inorganic salt 15%magnesium chloride, control 16.9 Brewers BCS/Mg Cl₂ 18.2 Fraction E/MgCl₂ 19.3 32% calcium chloride 7.3 26.3% sodium chloride 7.5

The last two figures were calculated from data in SHRP H-205.2. Theseresults indicate the appreciable improvement over the commonly usedsodium and calcium chlorides in ice melting characteristics whenFraction E and Brewers BCS are mixed with magnesium chloride. There isalso a 14% improvement over the control when Fraction E is used. This,together with freezing point depression improvement indicates that anappreciably improved deicing solution can be formulated.

The next stage of the investigation consisted of attempting to isolateand define the active components in the Brewers BCS. This was done byfirst filtering employing a 0.45 micron membrane followed byultrafiltration using a Model UFP-1-E-s (A/G Technology Corporation,Needham, Mass.) with a nominal cutoff at a molecular weight of 1000 andfinally gel permeation chromatography (GPC) using a Waters LC Module 1unit with a set of three ultrahydrogel columns and 50 mm Na₂ HPO₄solution at pH7 as the mobile phase. The brewers BCS liquor had twomajor carbohydrate fractions (a) a low molecular weight fraction withthe majority of components having a molecular weight of less than 1000,and (b) a high molecular weight fraction containing compounds with amolecular weight of 12,600 but with some components in the 1000 to10,000 molecular weight range. Fraction E was found to have achromatographic profile very similar to the low molecular weightfraction (a) above with a molecular weight of less than 1000. Cane SugarDCS liquor had more components than the Brewers BCS but had similar highand low molecular weight fractions with similar molecular weightdistributions.

In order to confirm that the low molecular weight fraction has thegreatest effect upon freezing point depression, a further series offreezing points were measured using in this instance, Dead Sea SaltSolution from Jordan in lieu of laboratory grade magnesium chloride.Again the concentration of magnesium chloride was 15% by weight for allsamples. TABLE 3 Freezing Point Sample ° F. ° C. Control: Industrialgrade magnesium −0.4 −18.0 chloride solution/Water Brewers(BCS) −31.9−35.5 Brewers GPC High Mol Wt Fraction −5.1 −20.6 Brewers GPC Low Mol WtFraction −16.4 −26.9 Brewers BCS Fraction E −13.4 −25.2

It was thus shown that low molecular weight (less than 1000)carbohydrates had the greatest effect upon freezing point depression.Based upon these experiments, it was concluded that the formulation ofdeicing/anti-icing compositions should employ compounds in the less than1000 molecular weight range such as those tabulated below in Table 4:TABLE 4 Carbohydrate Molecular Weight Glucose/fructose 180 Disaccharides342 Trisaccharides 504 Tetrasaccharides 666 Pentasaccharides 828Hexasaccharides 990

There is available commercially a wide range of carbohydrates withvarying carbohydrate compositions. An evaluation was conducted usingsimple sugars, disaccharides and polysaccharides in an attempt todetermine the effect of molecular weight and solute concentration uponfreezing point. The concentration of magnesium chloride used in the testwas 15% by weight. The test results for simple carbohydrates and complexcarbohydrates are tabulated below in Tables 5 and 6 respectively. TABLE5 SIMPLE CARBOHYDRATES Carbohydrate % Concentration of Freezing PointType Name Carbohydrate ° F. ° C. Control Mg Cl₂ (15%) Nil −4.7 −20.4Sugar Fructose 25.0 −8.9 −22.7 Sugar Fructose 50.0 −18.2 −27.9 SugarFructose 75.0 −31.9 −35.5 Sugar Glucose 30.0 −11.4 −24.1 Sugar Glucose65.0 −37.3 −38.5 Disaccharide Maltose 25.0 −8.3 −22.4 DisaccharideLactose 25.0 −11.7 −24.3

TABLE 6 COMPLEX CARBOHYDRATES Freezing % Concentration PointCarbohydrate of Carbohydrate ° F. ° C. Comments Control Mg Cl₂ Nil −4.7−20.4 (15%) Corn syrup- 30 −5.6 −20.9 Contains glucose, high maltosemaltose and maltotrisoe Corn syrup- 65 −19.1 −28.4 high maltose Cornsyrup 25.0 −9.9 −23.3 Average Mol. Wt. solids DE20 3746 Corn syrup 25.0−11.6 −24.2 Average Mol. Wt. solids DE44 1120 Corn syrup 50.0 −21.3−29.6 solids DE44 Corn syrup 65.0 −27.0 −32.8 solids DE44

It can be seen from the results above that glucose is better thanfructose and of the two dissaccharides lactose is somewhat better thanmaltose. The corn syrup DE20 has about 47% of mono to hexasaccharidesand the DE44 grade has about 69%, and the latter grade is slightlybetter in reducing freezing point. Also Table 6 shows that there is arelationship between carbohydrate concentration and freezing point thusallowing various formulations to be developed.

More complex carbohydrates were also evaluated such as dextrins andmaltodextrins which are derived by hydrolysis (enzymatic or via dilutemineral acids) of corn starch. In addition a series of thickeners wereevaluated. The control magnesium chloride solution was prepared from thehexahydrate in Table 7 below which shows the results obtained. Again allsamples contained 15% by weight of magnesium chloride. TABLE 7 %Freezing Point Compound Concentration ° F. ° C. Comment Control 15% MgNil +3.4 −15.9 Cl₂ Dextrin 5.0 −4.7 −20.4 Maltodextrin 5.0 −4.7 −20.4DE5 Maltodextrin 9.1 −17.1 −27.3 Lower Mol. Wt than DE15 DE 5Hydroxyethyl 0.33 +1.2 −17.1 Thickener cellulose 250 HHR Carboxymethyl1.0 +2.5 −16.4 Thickener cellulose Gum arabic 3.6 −1.8 −18.8 ThickenerGum tragacanth 0.2 −3.3 −19.6 Thickener 470

The Maltodextrin DE15 exhibits good results due to the lower molecularweight components present and the higher concentration. The higher themolecular weight, the less the influence upon freezing point. Somethickeners were unstable in the presence of magnesium chloride e.g.carboxy methyl cellulose, and so lose their efficacy as thickeners.

It is also important to define the chloride salt content fordeicing/anti-icing liquids, the higher the chloride salt content, thelower the freezing point and the higher the ice melting characteristics.These characteristics are shown by the data in Table 8 below for Mg Cl₂and Ca Cl₂ at varying salt and carbohydrate concentrations. TABLE 8Chloride % salt by % Carbohydrate Freezing Point Salt weight by weight °F. ° C. Mg Cl₂ 22.7 18.0 Less than Less than −47 −43.9 Mg Cl₂ 15.0 25.5−22 −30 Ca Cl₂ 29.6 18.6 Less than Less than −47 −43.9 Ca Cl₂ 17.5 4.1−5.4 −20.8 Ca Cl₂ 15.0 4.1 −0.6 −18.1

As the concentrations of salts and carbohydrates increase the freezingpoint of the mixtures decrease. In the case of calcium chloride at afixed carbohydrate concentration of 4.1% an increase of 2.5% by weightof Ca Cl₂ decreased the freezing point by 4.8° F. (2.67° C.). Againformulations can be varied to suit local conditions. Care must be takenas salt concentrations approach the eutectic point on the freezingpoint—concentration curve where the freezing point can rise and the saltcan crystallize out.

From the above discussion and laboratory evaluations the basiccomposition consists of at least the first two of the followingcomponents in aqueous solution depending upon ambient weatherconditions, terrain, nature and amount of freezing/snow precipitation,environmental concerns, etc:

-   -   (1) An inorganic freezing point depressant in the form of        inorganic electrolytes, mainly chlorides, but also others, such        as sulfates and acetates, and could be used in concentrations of        about 5 to 35 wt %. The main types employed are magnesium        chloride, calcium chloride and sodium chloride.    -   (2) A carbohydrate, especially lower molecular weight        carbohydrates in a range of about 180 to 1500. A preferred range        is about 180 to 1,000. The carbohydrates can be obtained        primarily from a wide range of agricultural based products such        as those derived from corn, wheat, barley, oats, sugar cane,        sugar beet, etc.    -   (3) Thickeners which are used in a concentration of about 0.15        to 10 wt % to increase the viscosity of the compositions so that        the liquid remains in contact with the road surface or with the        solid particles in piles of rock salt/sand, or rock        salt/aggregates, or rock salt alone, or sand or aggregate.        Thickeners are mainly cellulose derivatives such as methyl        cellulose, hydroxy ethyl cellulose, hydroxy propyl methyl        cellulose, hydroxy propyl cellulose, etc. or high molecular        weight carbohydrates.

The corrosivity of deicing/anti-icing liquids is important due to theeffect upon automobiles, other road transport vehicles, bridges,reinforcing rods (rebars) in concrete structures such as bridge decks,ramps and parking garage decks.

The testing of liquids for corrosivity can be quite complex and thereare a number of tests developed by organizations such as ASTM and theNational Association of Corrosion Engineers (NACE). The test conditionsand metals must approximate those experienced in practice such asaerobic conditions and cold rolled steel specimens. Prior art testsusing nails immersed in liquid contained in a screw top bottle are notmeaningful mainly because of the anaerobic conditions and the variationin metal substrate composition, the degree of cold working andcleanliness.

Satisfactory test methods include SHRP H205.7 Test Method for Evaluationof Corrosive Effects of Deicing Chemicals or Metals (Handbook of TestMethods for Evaluating Chemical deicers SHRP—H332, Strategic HighwayResearch Program, National Research Council, Washington, D.C.) And thetest described in the Deicer Specifications for the Pacific NorthwestStates of Idaho, Montana, Oregon, Washington. The latter is based uponthe NACE Standard test Method for the Laboratory Corrosion Testing ofMetals. TM0169-95.

Some corrosion rate results employing SHRP H205.7 showing corrosioninhibition due to carbohydrate presence are tabulated below in Table 9.TABLE 9 % Chloride % Corrosion Rate (mils per year) Salt CarbohydrateOne Week Three weeks Six weeks 15% Na Cl Nil 5.97 4.66 5.48 15% Mg Cl₂Nil 2.58 1.93 1.73 15% Mg Cl₂ 4.1 0.89 0.61 0.40

As can be seen from the data in Table 9, the carbohydrate magnesiumchloride formulation reduces the corrosion rate of steel by 92.7% ascompared to sodium chloride alone and 76.9% as compared to magnesiumchloride alone. Formulations as shown in Examples III and IV (q.v.) weretested for corrosivity employing the Pacific Northwest States protocoland there was a reduction in the corrosion rate compared to sodiumchloride solution of 57.2% for Example III and 40.4% for Example IV.This again shows corrosion inhibition properties.

The following examples are exemplary of various specific embodiments ofthe present invention which are useful as deicing agents: Component Partby Weight Corn Syrup Solid DE 44 22.5 Industrial grade magnesium 50.0chloride solution* 2% Methocel Solution 2.0 Colorant (Caramel YT25) 0.5Water 25.0 Freezing Point (ASTM-D 1177-94) −12.5° F./−24.7° C. Viscosityat 77°: 20 centipoise Appearance: Gold color, clear solution Odor: Mild,pleasant*Note:Industrial grade magnesium chloride solution is a commercially availablemagnesium chloride solution also containing calcium chloride, sodiumchloride, potassium chloride.

*Note: Industrial grade magnesium chloride solution is a commerciallyavailable magnesium chloride solution also containing calcium chloride,sodium chloride, potassium chloride.

Example II

Component Parts by Weight High maltose corn syrup 31.5 Industrial grademagnesium 50.0 chloride solution Colorant (Caramel YT25) 0.5 Water 18.0Freezing Point (ASTM-D 1177-94): −22° F./−30° C. Viscosity at 77° F.14.4 centipoises Appearance Gold color, clear solution Odor Mild,pleasant

Example III

Components Parts by Weight High Maltose Corn Syrup 22.2 Industrial grademagnesium 70.0 chloride solution Water 7.8 Freezing point (ASTM-D1177-94) Less than −47° F./−43.9° C. Appearance Clear, light brown,mobile liquid Odor Mild, pleasant Specific gravity 1.27 Viscosity at−94° F./−70° C. Heavy syrup, flows

Example IV

Component Parts by Weight High Maltose Corn Syrup 20.5 43% CaCl₂ 72.3Water 7.2 Freezing Point (ASTM- D 1177-94) Less than −47° F./−43.9° C.Appearance Clear, colorless, mobile liquid Odor Mild, pleasant SpecificGravity 1.33 Viscosity at −47° F./−43.9° C. Very heavy syrup

Example V

Component Parts by Weight High Fructose Corn Syrup 19.55 43% CalciumChloride Solution 73.15 Water 7.30 Freezing Point (ASTM- D 1177-94) −31°F./−35° C. Appearance Clear, colorless, mobile liquid Specific Gravity1.38 Odor Mild, pleasant

Example VI

Component Parts by Weight Glucose 32.5 Industrial grade magnesium 50.0chloride solution 2% Methoeel Solution 2.0 Colorant (Caramel YT25) 0.5Water 15.0 Freezing Point (ASTM- D 1177-94) −38.2° F./−39.0° C.Appearance Gold color, clear solution Odor Mild, pleasant

Colorants may also be used to enable applicators to see where the deicerhas been deposited. Non-toxic colorants which may be used includecaramel solutions and food grade dyes.

In a further embodiment of the present invention it is desirable to usesugars in combination with a chloride salt. For purposes of thisinvention sugars include mono- to decasaccharides which have molecularweights from 180 to 1638. Sugars within this molecular weight range havea synergistic effect upon freezing point depression. Beyond thismolecular weight of about 1638 the synergistic effect rapidly decreases.

Note that for substantially the same concentration of MgCl₂ that thethree formulation using sugars exhibited a lower freezing point thanMgCl₂ alone. TABLE 10 Viscosity Mg Ford Cup Freezing Concen- Chloride %No. 4 Point tration by Weight (Sec.) ° C. ° F. Maltodextrin No. 5 5.0415.0 13 −20.4 −4.7 Molasses 18.8 14.9 13 −24.9 −12.8 Maltodextrin No. 159.1 15.0 11 −27.3 −17.1 Aqueous Magnesium None 15.0 — −15.9 +3.4Chloride Reference Solution

Mixed sugar solutions are obtained commerically by the hydrolysis ofstarches and other polysaccharides obtained from corn, wheat, rice etc.A wide range of products are available which are defined by the DextroseEquivalent Value (DE Value) and the saccharides distribution in thehydrodyzate solution. The Dextrose Equivalent is a measure of the amountof simple sugars i.e. mono- and disaccharides, and typified by glucose,fructose, maltose, sucrose and lactose. Pure glucose has a DE Value of100. The saccharides distribution uses “DP” as a shorthand term for thevarous saccharides e.g. DP1 is for monosaccharides, DP2 fordisaccharides and so on.

The Maltodextrin No. 5 is a hydrolyzed product having a DE 5 value andhas the following saccharide distribution i.e. mixture of sugars: TABLE11 Saccharide % by Weight Molecular Weight Mono - DP1 0.9 180 Di- DP20.9 342 Tri- DP3 1.0 504 Tetra- DP4 1.1 666 Penta- DP5 1.3 828 Hexa- DP61.4 990 Hepta- DP7 1.5 1152 Octa- DP8 1.4 1314 Nona- DP9 1.4 1476 Deca-DP10 1.3 1638 Undeca- DP11 + 87.8 —

The grade of molasses listed in the Table is Molasses No 677 availablefrom International Molasses Corporation Ltd., of New Jersey and has thefollowing analysis: Fructose 7 to 11% by weight Glucose 7 to 11% byweight Sucrose 30 to 36% by weight Total sugars 45 to 52% by weight Ashi.e. inorganic (phosphates, 11.5% maximum Ca, K, Mg, Na) Cellulosics,high mol wt. compounds 16 to 23% by weight Total Solids 79 to 80% Water20 to 21%

The molecular weight of the carbohydrate for the molasses used isbetween 180 and 342. The weight average molecular weight for molasses isbetween about 280 and 290 depending upon the saccharide mixturecomposition.

The Maltodextrin No. 15 is a hydrolyzed corn starch product having a DE(Dextrose Equivalent) of 15 having the following saccharide distributioni.e. mixtures of sugars. TABLE 12 Saccharide % by Weight MolecularWeight Mono - DP1 1.3 180 Di- DP2 4.1 342 Tri- DP3 6.0 504 Tetra- DP44.6 666 Penta- DP5 5.2 828 Hexa- DP6 7.6 990 Hepta- DP7 6.3 1152 Octa-DP8 4.4 1314 Nona- DP9 3.5 1476 Deca- DP10 3.0 1638 Undeca- DP11 + 54.0—

As the hydrolysis of the polysaccharide solution is allowed to proceedValue increases as does the low molecular weight sugars: TABLE 13 %Concentration By Weight DE Greater Value Product DP1 DP2 DP3 Than DP4 5Maltodextrin No 5 0.9 0.9 1.0 97.2 15 Maltodextrin No. 15 1.3 4.1 6.088.6 25 Cleardex 25 AE/42 5.0 6.0 11.0 78.0 36 Cleardex 36/43 14.0 11.010.0 65.0 43 Cleardex 43/43 19.0 14.0 12.0 55.0 52 Cleardex 52/43 28.018.0 13.0 41.0 60 Cleardex 60/44 IX 31.0 36.0 10.0 23.0 66 Cleardex66/43 40.0 35.0 8.0 17.0 97 Cleardex 95/37 95.0 3.0 0.5 1.5

Here Cleardex is a trademark of the Cargill Foods Corporation.

The low DE Value materials give higher viscosity solutions than the highDE Value solutions whereeas the latter have a greater synergistic effecton freezing point depression. Combining these effects allows appreciableflexibility in formulating deicing and anti-icing compositions.

While the present invention has been particularly shown and describedherein with reference to various preferred modes it will be understoodby one skilled in the art that various changes in detail may be effectedtherein without departing from the spirit and scope of the invention asdefined by the claims.

1. A method of forming a de-icing and anti-icing composition whichcomprises: (a) providing an aqueous solution which contains a lowmolecular weight carbohydrate, and a chloride salt, and (b) applyingsaid aqueous solution to a source of particulate material selected fromthe group consisting of salt, sand and aggregates, and mixtures thereof.2. The method of claim 1 in which the carbohydrate and chloride in saidaqueous solution are present in the following concentration: Weight %Carbohydrate 3 to 60 Chloride salt 5 to 35 Water Balance

and where said carbohydrate has a molecular weight in the range of about180 to 1500, and is at least one selected from the group consisting ofglucose, fructose and higher saccharides based on glucose and/orfructose and mixtures thereof.
 3. The method of claim 2 in which thechloride salt is at least one selected from the group consisting ofsodium chloride, magnesium chloride and calcium chloride.
 4. The methodof claim 2 in which the aqueous solution has a viscosity of about 0.1 to3 poises at 25° C.
 5. The method of claim 1 in which the aqueoussolution has the following composition: Weight % Carbohydrate 3 to 60Chloride Salt 5 to 35 Water Balance

and where said carbohydrate has a molecular weight in the range of about180 to 1000, and is at least one selected from the group consisting ofglucose, fructose and higher saccharides based on glucose and/orfructose and mixtures thereof.
 6. Applying the coated particulatecomposition of claim 1 to an outdoor surface.
 7. A method of forming ade-icing and anti-icing composition which comprises: (a) providing anaqueous solution which contains 3 to 60 wt % of a low molecular weightcarbohydrate and 5-35 wt % chloride salt, balance water, and (b)applying said aqueous solution to a source of particulate materialselected from the group consisting of rock salt, sand and aggregates andmixtures thereof whereby said aqueous solution forms a coating on saidparticulates.
 8. The method of claim 7 in which the chloride salt is atleast one selected from the group consisting of sodium chloride,magnesium chloride and calcium chloride.
 9. The method of claim 7 inwhich the aqueous solution has a viscosity of about 0.1 to 3 poises at25° C.
 10. Applying the coated particulate composition of claim 7 to anoutdoor surface.
 11. A method for reducing the buildup of snow and iceon an outdoor surface, comprising: applying to the outdoor surface acomposition comprising: an aqueous solution which contains mixtures of acarbohydrate and a chloride salt in which the constituents are presentin the following concentration: Weight % Carbohydrate 3 to 60 ChlorideSalt 5 to 35 Water Balance

and where said carbohydrate has a molecular weight in the range of about180 to 1500, and is at least one selected from the group consisting ofglucose, fructose and higher saccharides based on glucose and/orfructose and mixtures thereof.
 12. The method of claim 11 in which thechloride salt is at least one selected from the group consisting ofsodium chloride, magnesium chloride and calcium chloride.
 13. The methodof claim 11 which further includes a colorant to provide visual aid inapplying the composition to a surface.
 14. The method of claim 11 inwhich the molecular weight of the carbohydrate is in the range of about180 to
 1000. 15. The method of claim 11 in which the composition has aviscosity of about 0.1 to 3 poises at 25° C.
 16. A method for reducingthe buildup of snow and ice on an outdoor surface, comprising: applyingto the outdoor surface a composition comprising: an aqueous solutionwhich contains mixtures of a carbohydrate, a chloride salt and athickener in which the constituents are present in the followingconcentration: Weight % Sugars 3 to 60 Chloride Salt 5 to 35 Thickener0.15 to 10 Water Balance

and where said carbohydrate has a molecular weight in the range of about180 to 1500, and is at least one selected from the group consisting ofglucose, fructose and higher saccharides based on glucose and/orfructose and mixtures thereof.
 17. The method of claim 16 in which thechloride salt is at least one selected from the group consisting ofsodium chloride, magnesium chloride and calcium chloride.
 18. The methodof claim 16 in the molecular weight of the carbohydrate is in the rangeof about 180 to 1,000.
 19. A method for reducing the buildup of snow andice on an outdoor surface, comprising: applying to the outdoor surface acomposition comprising: Weight % Carbohydrate 3 to 60 Chloride Salt 5 to35 Thickener 0.15 to 10 Water Balance

and where the carbohydrate has a molecular weight of about 180 to 1500,and is at least one selected from the group consisting of glucose,fructose and higher saccharides based on glucose and/or fructose andmixtures thereof, and where the thickener is selected from the groupconsisting of high molecular weight cellulose derivatives andcarbohydrates in the range of about 60,000 to 1,000,000 for cellulosederivatives and 10,000 to 50,000 for carbohydrates, with saidcomposition having a viscosity in the range of about 0.1 to 3 poises at25° degree. C.
 20. The composition of claim 19 in which the chloridesalt is at least one selected from the group consisting of sodiumchloride, magnesium chloride and calcium chloride.
 21. The compositionof claim 19 which further includes a colorant to provide visual aid inapplying the composition to a surface.